asthma

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Description: Asthma is a lung disease or rather a disease of the bronchi, that causes cough and breathlessness which is associated with a characteristic wheezing sound. The inspired air streams through the bronchi into small vesicles -- the so called alveoli. There, with the constant in- and expiration, our blood is supplied with oxygen and carbon dioxide is exhaled.
In asthmatics mostly an allergic reaction takes place within the body that is triggered by pollen or other particles. One speaks of "allergic asthma" -- the so called bronchial asthma. In those cases the body judges inhaled substances - like pollen - as dangerous. Large quantities of antibodies are produced which leads to different reactions within the bronchi. On the one hand muscle cells lining the bronchi are triggered to contract, the airways narrow and less oxygen reaches the alveoli. Exhalation is also more difficult. On the other hand more mucus is produced within the bronchi which leads to further narrowing of the airways. The cilia are impaired and hence also the clearance function of the lung.
These inflammatory reactions can increase the narrowing of the bronchi to a life threatening extent. Most asthmatics suffer from allergic asthma. In non-allergic asthma there are the same inflammatory processes as all asthmatics suffer from airway hyperreactivity to different stimuli. Drug therapy for asthma includes bronchodilating substances that are administered with inhalers. They relieve the dyspnoea caused by the muscle contractions.